<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>
<body>
  <!-- 容器 -->
  <div id="test"></div>

  <!-- 引入react核心库 -->
  <script crossorigin src="https://unpkg.com/react@16/umd/react.development.js"></script>

  <!-- 引入react-dom 用于支持react操作dom -->
  <script crossorigin src="https://unpkg.com/react-dom@16/umd/react-dom.development.js"></script>

  <!-- 引入babel，用于将jsx转为js -->
  <script src="https://unpkg.com/babel-standalone@6/babel.min.js"></script>

  <script type="text/babel">    /* 此处一定要写babel */
    // 1、创建虚拟dom
    const VDom = <h1>hello, word</h1>     /* 此处一定不要引号，因为不是字符串 */

    // 2、渲染虚拟dom到页面   ReactDOM.render(虚拟DOM, 容器)
    ReactDOM.render(VDom, document.getElementById('test'))
  </script>
</body>
</html>